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Optimal diagnosis and management of stroke in young adults benefit from a multidisciplinary team, including a vascular neurology specialist. In addition to the "standard" vascular risk factors including smoking, hypertension, diabetes, and hyperlipidemia, one needs to consider alternative etiologies including substance abuse, carotid/vertebral artery dissections, and rare genetic conditions among others. Once a young patient is determined to have had a stroke, the next question a clinician should ask is why did this patient have a stroke? A "heart to head" diagnostic approach is recommended. A thorough history is performed, including a detailed family history with specific annotations on each family member. A thorough physical examination is necessary including a careful evaluation of the patient's general appearance, noting any joint laxity, and/or abnormalities of the skin, eyes, and heart. Findings across multiple organ systems in the patient and/or their family may indicate a genetic etiology. After an initial head CT rules out hemorrhagic stroke, additional testing should include a brain MRI, neck and cerebral vascular imaging (e.g., CTA for head and neck), transthoracic echocardiogram with a bubble study, telemetry monitoring, basic risk factor blood work (e.g., lipid panel, hemoglobin A1c, TSH, ESR, CRP, RPR, HIV, and toxicology screen), and, when appropriate, sickle screen and pregnancy test. There should be a low threshold to obtain blood cultures or a lumbar puncture. The acute treatment of ischemic stroke in young adult patients does not differ from treatment of older adults, using intravenous alteplase within 4.5 h, assuming no contraindications. In suspected proximal large artery occlusive disease, interventional clot extraction procedures should be employed in patients deemed eligible. Long-term secondary prevention strategies aimed to reduce recurrent stroke risk by targeting and modifying vascular risk factors should be instituted. The mainstay of preventative therapy is aspirin for most etiologies; however, for atrial fibrillation, anticoagulation is recommended. Statin therapy is another pharmacologic intervention recommended in most stroke patients. Other measures employed are blood pressure reduction, smoking cessation, optimal glucose control in diabetic patients, the initiation of a healthy diet and regular exercise, and lastly, substance abuse counseling in appropriate patients.

Cerebral venous thrombosis (CVT) is a less common cause of stroke that is an often under recognized entity in clinical practice. The goal of this chapter will be to provide clinicians with the knowledge to succinctly recognize the various presentations of CVT, emphasizing rapid diagnosis and the potential treatments necessary to produce optimal clinical outcomes. Detailed descriptions of the relevant anatomy and associated clinical syndromes will be discussed. Detailed sections regarding CVT epidemiology, pathophysiology, etiology, diagnosis and treatment will be provided. Prognosis and long-term follow-up will also be discussed. Relevant literature will be cited and clinical trials across the spectrum of CVT will be highlighted.

Stroke in younger adults is less common than in older adults, with approximately 10-15% of all strokes occurring in adults aged 18 to 50 years of age. The pathogenesis of stroke in younger adults requires additional considerations for several less common risk factors and etiologies. As with any stroke patient, a thorough workup including evaluations of the brain, the blood vessels of the head and neck, the heart, and basic bloodwork must be performed. On the basis of these results, as well as case-specific clinical findings, family history, and other considerations, additional testing for genetic or hypercoagulable causes and specialized vascular and echocardiography can be performed. Overall, it is critical to identify the likely pathogeneses to prevent stroke recurrence. Regardless of pathogenesis, young stroke survivors with high rates of traditional risk factors must have these risk factors aggressively managed for long-term risk reduction. In this chapter, we focus on ischemic stroke in the young emphasizing a clinical evaluation framework, describing key considerations regarding etiology, treatment, and prevention that providers should contemplate in course of individualized patient care.

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Structural analyses of mechanisms with components that move relative to each other provide a unique problem to the analyst building and running structural models. In these situations, the analyst usually has to either simplify the problem to a point where the results are unusable or maintain multiple models, which will take more effort to maintain and more resources to run the models. If a mechanism is simplified down to just analyzing one component at a time without regard for the other components in the system, the results will not be accurate because the loading effects of the other components will not be accounted for. In cases where all the components are included in the model the loading effects from the other components will be accounted for, however, a separate model will be required for each position. This paper presents a method of breaking down the complex mechanism into a component level model for each part of the assembly, while still accounting for all loading effects of the other components; in the Pivot Method the component under analysis stays stationary and the loading moves around the component to represent the different positions that it can take. In order to accomplish this task, a simplified model is used to generate loads at each of the joints. Once the pivot loads are known, a spreadsheet can be used to transform the loads to a coordinate system in which the individual component is being modeled. With the pivot loads known and all the loads transformed into the proper coordinate system the structural analysis of the component under investigation can continue. The intention of this paper is to introduce the Pivot Method and to demonstrate that it provides a good trade off between both the complexity of methods that model the assembly as a system, and those that focus on the component under question alone. To accomplish this, the analysis results of the Pivot Method models will be compared to results obtained from other methods, with the intention of showing that the Pivot Method will provide the same results while requiring less effort to model and less resources to run.

sector operators will also have to factor in developments under the Consumer Rights Directive. Article 19 of the Directive states: Member States shall prohibit traders from charging consumers, in respect of the use of a given means of payment, fees that exceed the cost borne by the trader for the use of such means. Assuming the Directive is approved by the Council of Ministers when they vote on it this month (July 2011), this means that payment card surcharges will be limited to no more than passing on the actual cost to the trader: no element of markup will be permitted. It is currently proposed that the Directive would require transposition into local member states ' laws by the end of 2013. In the meantime, expect yet more small print disclosure in advertisements, along the lines ' Credit card surcharge applies ' , and widespread adoption of ' Payment method charges ' sections within traders ' websites.